Samenvatting

Citizens investigating crimes themselves is a growing trend, because of democratization of information (e.g. social media), tools (e.g. apps) and knowledge (e.g. explanimations on YouTube). More and more citizens do their own research as modern Sherlocks. The police has to handle these trends in line with participant wishes and the law, but does not yet have concrete tools to do so. This article explores how the police participate in contemporary citizen criminal investigations, including the difficulties and benefits experienced. The obtained insights of the presented research serve as guidance, which can help police officers understand how to participate with citizens who have started, or want to start, a criminal investigation. The presented model explains how police can use it to better guide and stimulate, but also stop or protect citizens in their investigative activities. An app with professional guidance was piloted in four police units to participate with citizens that do their own research and learn from expectations and experiences. Citizens need guidance, but more importantly expect a certain degree of reciprocity in collaborating with police in criminal investigations.